SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0da869bf94ee9b54ea27221e5384eef0fe32bc2b26fe37dd468353062f8c6a66' 
  AND token = 'N4rnu4ETNeMIYem9U+28tTTLUevMqJ8J0nsrt7AUuAA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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