SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '46c0dc3982d2b82d2c269623d949095ad1a888467dc6cb42ceb4e16903049c91' 
  AND token = 'w3HdyzhqHyJaIrJWsXB8JXCQuRbwtwyPw2awbx7Lqxs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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