SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0fc7db32595954f50c8440484d98596df4ef9750e33ebace7b76546902dcbde0' 
  AND token = 'rfXO5ge4UiFWYsLYK6UsL1zORncyXBpAhoSkF8I6PgU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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