SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64a641b7cbd9d2296d565efe13d50405b85d96e787ffdbd9fa1450513b19a22d' 
  AND token = 'eIy4/uOd7rWREKr+nETGlI3jHyoLmmQPv4LRghysjM8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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