SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eb7d1364b8947b93e70b82daccf32f65b38302c0474c55ef4f9c12eaaf5c38a2' 
  AND token = 'pnSFh5PLIk5t1v6Wve/DkPjGAwIW/dXrgb25gyOx3LA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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