SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ede6a3d397a08b329b455a81ae47510f2a258e89038dbb776b0fadd988467b27' 
  AND token = 'bDSTMOnj4EiYjQpk8pzsO6ek0hgEM9uZcxSCMXNcfmc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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