SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64caf40fc162da87baad0c9530b244556bae8c08d8d95c4b54da8c19da416a27' 
  AND token = 'MLheB3psaNZPXnvWfxU01TrFWC6naPDftE9BWuJTLrQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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