SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '26d01b85060afd960a8b09031ba1d0510f0812d234869038527c168dc05a4e06' 
  AND token = 'wXBvcazSMxOyLRXyiL11dEvnIib7hvumZVbLuKPpP3I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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