SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b6319fa4ecbbe303295c6f20d351325e35fded5b54d8a3021e77cb1158c56bc' 
  AND token = 'PaMC4k9zSS8PHjT/Cymaz/X38psy6OnCfWlsh/Oi0co=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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