SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da4a2e72c7e3abba9de1403b453a6341c0fea43c824539cb363a634a78933209' 
  AND token = 'b0LUxA9M6qUovPvriTHAzKmlzqmpEVOGMDiuuzBVZlw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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