SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da87fde3a117228a791d03b595d254f9470bd9598585323bf6cd28721b3d147b' 
  AND token = 'EMPMcwOpDlKJ+EyIqYIjiRPmF/gii3OfMmQTZUL167c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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