SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '56ec95685c6030e72f833f9f6b823ee2ef4ada15b25aa2f3ef31c7bf1658c02d' 
  AND token = 'E1mpbr4jHHk/JXHZO/7t8DvvV/d4DgHUUeqFwxAZ5Ag=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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