SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '259368b864d9dea3415544c82485c9c13468870c0dfe0ec66fd9427885fe98b3' 
  AND token = 'NE/G4E1oA8AsmgDrjMj/2k0awos9NNr/OXv3HKx66D4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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