SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2de1b05942c082342b21dca7ae80bfa517fac62a36f48dcc7f942fa7b1d5ad6' 
  AND token = 'BAXzEr1k09JP9psCoTxboSHSsRnMpv2XeoFfrEbPbrQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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