SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cdae2d6e23a3f4711fb7995d826a74ef96739dff6c2453c9c43c68d495d45aa8' 
  AND token = 'T2ZzWv1PAhYNs6tBoGGc/eYTJ5c/aXAFp+/dXgrRDL4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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