SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '75f2e7ad28326d68edc39d1b30c2dacab4d6f08b575c3d0ba73b027e0ed594a2' 
  AND token = '8W1b6nzDxlul0C5fCuUzVo1WWkA+gTMLKClbAXGbhqA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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