SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a1b9245d393b2c1358e2cdbe5ce87f2a98b084ed20352201994c4286e1af91ed' 
  AND token = 'I5YlwgdEqex5oKgibAgWNOFI0gk19KfOOEp5ASowvPU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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