SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a7fdf4ed3987f9fd494633c23cff7fac26a7121249e97b298a58620f7305208c' 
  AND token = 'jrh1BTuULUgMabncco6V6iIsHX0056zj07dfxQFxNHM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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