SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c56233006651ab4842dc47fa1ce30454c2613ce02a5a7381f0c58c25938e5918' 
  AND token = 'nOFBlls6r58p+IY/wzIU05slZ5bPQauvXhpKLhCvoV0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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