SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d22df131dfea139f1fddfc2eda173e18303df9305fb3278288a0758b2d2e80f' 
  AND token = 'TL91jKp9a6Y+YjGEUPIwMsEFSUPVcLAdYawrnCWL0Qs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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