SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0c993a519313f1a11800677489f50cb420c7cf0966243a115419de041dba60a9' 
  AND token = 'kNW1glj0U/vhT2IZvzOmDmhGLDhkEJqwxhw20NDgzHo=' 
  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"
    }
  }
}