SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58c7cfc79175f55ad66719ac2260146bae18c978abe2eef096d8c415ccc486ca' 
  AND token = 'd0MIMGXMxIFCfHkz8CCbXR8q4wnHL0778ZTEJtGmdH4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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