SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd94282aeb48da6d2192f1110b54e9a209cf354669b38c1a0bc0727ff7c57d43' 
  AND token = 'gvomYuAk1lxCXZ1RQaGK4J5aMYeh34GJu0ujEBX5O9c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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