SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eb0007c23a95ac65011606254d44ab46350405366ba97d26d8650ecf14330c18' 
  AND token = 'O1Vx9TiWFNQqzQWXfAWvRhfC6e5dIooImiAjWfHCd4I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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