SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cb751f802c7d8ee5d9d84970e3d2419d80ce7134ee8b843df7206a7507a07ee8' 
  AND token = 'Y9wssmF5hEnNvHmBkFGlvGa//tXDTYBblTy+baiYxvg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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