SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7c41e53185b921c39a97768e2405d6f16550457aafc609b595d07a28e867d784' 
  AND token = 'DgPZwrRyvFJUpw05DG1jWL+oQ4r5tXwChdfRDYKlt3s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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