Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ef635ef73ddb4d666d3c87d9a88afaf0c20d8560b8f33f8dde3346771d86ca48' 
  AND token = 'vDJXtoDxlnugXw4XiZ8xRZYk1f4BAz1Juz/Sb/ZQn2k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}