SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f47e9ac272f95b0b02eaa6efa86016bef82730d2b8ee2c2bd15cdbef6e16ed55' 
  AND token = 'H6eZfiug14M1HKs35WTLIAZTwahQNW99qolqPCwsyKY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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