SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e10c992bc7f6feeaefd0f3fb4c342afcf36e7d02bc348faa625cc0c0fd3170c' 
  AND token = 'z8v+yndoAeOZSPFEMcOaOC3/kM+ctCjucGUp20z/73Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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