SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bb793be8d36afdbfc7d8515c296122a2f87cb9e86bae36b8e94ab84e668ad738' 
  AND token = 'yZrJM0BgTUkjATCwazts7OVMrIwW+bOLwJwjCBq2Fu8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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