SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b150c017bfca9e61b4f1f386d29062437f5ea1942b49b8fde2e8737a3ab7451c' 
  AND token = 'FHPPWsXoTV8/VTs0dPgSC+0+XNL1KKAGIeBrjaO12Hs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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