SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a87fab6e8ffe1ace93acff93afa26879ee52262d8dd4abc01e93ade97518fd71' 
  AND token = '10HjzV/Mwc0g2hZGBqbwUvxJgbCSfW+xpP3LSU20T/0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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