SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '65b218698767c1471a39fb9a1225a3930150aaf24fb72c2344936e52245338bf' 
  AND token = '3hczKeZ+lVVMfY9lu3FKNR10fyq3u6GQGLkqphd/4C4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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