SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed893d5fad6b71bc14541dcc2f22f83bc53877cc4424c391387afd6869f00396' 
  AND token = 'zRLPG4CqDzgJmhke0lga2Mwwg8WwSOBl1Gh33sIKOfI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}