SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0cdabc00f49eb4c39180652d8311a8c96f1223f0c4d992e661f28f7d520397e7' 
  AND token = 'BAGFNxLwUcWtW5I+kaxvcXn35mX5DpI6jNOYQ2eEoQ8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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