SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '46afb9a778e19b633553d623b4fb06e5630d718ebaa3c834c916e3153964045a' 
  AND token = 'KAn9P+TKpSSCNo3hUh0LxjHBlRuSy5KrEI9lSZopLec=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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