SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '95e77e169caabc4b86daf31602e08d18e6ce0f498cacc623bc963d63ed12cc31' 
  AND token = 'ojoXs0kDg6uW+P2e/aAx+TY7IqQwbqNJpJtXoOIiDE4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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