SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'abb829ecfdc98b155643f3fac8a844ea2f167f548d8e74aeca2e5129d829b4e3' 
  AND token = 'CJvcu9QTqjd6//5dkjHPbZGrweMAC6Vi/j3+YIHftAg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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