SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa1119b998b52af4150dfefce27c19cb90a4ba6bd0ef62b426e918f19a734c04' 
  AND token = 'DO2WZZT8PMyZAFLz+Fy3IogGlSVS4UcmWL0hupCxKQQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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