SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b85a6b5597032eb07001aa649d60e8f399d724fe70752ff379fc36bccc2c017e' 
  AND token = 'obOasjKFHcIe3/e5jQHdNT34RhE3Z5wxHh2yPwEqjkg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}