SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5235fd9490335a36849ef102fcaad8f49e1021a5d741bba507970932bb8f9e8f' 
  AND token = 'VqmpOKMn/LZ8FdMzR4R95k1jqzMXWahojFKtN5Njg3I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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