SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6cd648377803b8684ba08044bfc21c0a9ca56cf6d71798795df276f3e4cf047d' 
  AND token = 'wbz6KmfFohWhoQ+ZzvHMnXnvHvUQX44L161jPYoL3tE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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