SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b9b93486b2cb2265847ddcb64fe7a37f546cc6ecb4ebf1d4da9257e66d45874' 
  AND token = '3gRzbD7Uycz4JuA1k5OLhdshQfpKjj7JXJksMEI1po4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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