SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e6732cecdd900187937352232153c52bca623f0e1acbc40f5577bbcc4ac0cc0f' 
  AND token = 'fzpUSp5L24RPzYLfwa3eeOwuCdVQai8UfsliFLCSeVA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00065

JSON explain

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