SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '927b2b40d55d29254c6c5e567b6182f38ddc1c2c42109f6ddbb9bab17772c8ef' 
  AND token = '42BcmDLKMOVKvqJ1Go7iohs1KKiBLq8U7pYjgROutL8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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