SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '23ecedca394fb166146bb4dc524d767c5dd326ebf9c2e19fb1483542fe7391a2' 
  AND token = 'wSOGJwvQJ2JSGwbZKWeuXGwy4g5ARMoT4nu/6QwlMdA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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