SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a7380fb86564ee5ce34023c8d35e5b4988dea0f1955198307598ea7fdb357c8a' 
  AND token = 'U8R2yEs1Dk9oDAXOtkuHUoguB1iTyArFWnZiupO58iY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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