SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f74565926fe66428a5535cd8062c081bba18b38adc9893d35ff1a518e66bc34c' 
  AND token = 'gGqWMdRlwMT2HGyuPuQgfgmZefpWaRBJveOq4UtGi2w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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