SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '22103bda08dcf8ed48f4038e2ca7234e48ac32b0ea55914dc979469c0a7c99f8' 
  AND token = 'wLLuHOeLzRDPH6b04bnql2L36YMz9QIZiJ3XOo3rWSQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}