SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a4619eaf06537285283bf79544530a67945d08cd3c945cf4f0982390152e4794' 
  AND token = 'lnQn9iQAKvdtkC+NFFSctY0MewYU0teZfZfJI5F6iQE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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