SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7d13bde51e733aa04af060d46c7cb840f5ab3db71bd07d7868787ad0bb14fdf9' 
  AND token = 'Q7GRMuZxXCr+2y3C+bUJmhK1XiBthxkR36nCknSET4o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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