SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2d8200b8778d1b6da45b11a0b1a793981bd29ee93f8f51e47cefe519677309ce' 
  AND token = 'lpWCBFa8a2hMYHN+M2P3w74afN92joK67lDkikA78ns=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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