SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd30dcfa4ac99d9e22075f830bc95a9215c87c88ce5aece65bf1f586845019b1' 
  AND token = '2LI3wNNdG4A9ugjNn9q7J/B+NGRcr/9L10NTmBJkwU8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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