SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '294ffbd9eb7c95fdfbb3e45a2b7ced9b1d8a49abcef632649bbf05e52f7281b5' 
  AND token = 'fRGi1h68JPXe9tUVK0P61SpQKqTjXlvDr+4Jxm1jW78=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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