SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f3e05411e93f844cfcc91caf0ca35b79e37a1db6024e493cbf3bbc566eff10e4' 
  AND token = '1aLmcNFqQjz4nlwqdg9OEcP5391J2tretV7y83uXpWI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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