SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bddc13e16dd7c6e27f6d9d7df443984e9d3339192fad7e18448659f1cf9652ca' 
  AND token = 'TsdmhUHagS7w88nw5T4XFuvn3XcJLx0CtXuzsO+hvCA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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