SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '654f6e6dfa0db533a4c40f6e599bac3fff826785d453abd4670e2771313c63d0' 
  AND token = 'QFEy/+QQuMYJSFCCDzMuZr+lhq3GD/VCZnDLSBPxMuE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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