SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e4411cb66d30af9aca132a37ead0ee1fbeb322487f7d795080b4d9c73ec0a366' 
  AND token = 'WBAkrYR1gDnn89zYyF2D3NTcGStvgCUFvgKMTNAvK4o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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