SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c171a7cff454297e3d09694f12b674e17d63523edbd49eb364ac5302dc534ac7' 
  AND token = 'W7gXYjFUK/6kwjo0MKq8U+ku50tCRlvHHQ52s9ctYzg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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