SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e1a01c23e22d21e8898659af636ffb1f4c2bfd8fa20d0437c069fd0db967c73' 
  AND token = 'R3P7L1BKOMrnBDZ7ty98zzZAYDbNU2Fg8SYKCjL/neM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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