SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1be4c8d04eb3dd9f498916f14de10cf3fa5747f25e6decf357d3b557d5516786' 
  AND token = 'EI2zV8lVZWEZblccBfeSr6Ddv4KbsdNwoJvOFGDHe5o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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