SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3f363d4a0db77bf13a84c9c74518b7ce1936d9b0a4d37a5a7b6fe679fb5fd8a5' 
  AND token = 'jAt3Gvb3vjgpgC6LL0p5+/japzHI7wAsTUQ3smMolnI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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