SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '98abbedf34d7a541be6ad215446a42126b969ecb0a601f7c7b8f4013326e1b44' 
  AND token = 'JOTN3wQJvGLdVHpsopAHkGOsfFhy96l+qCch4B3Hrrc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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