SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0efaa3b33af99e3395b6fdc63e36072ecc9c8715a20fcf99f558c0b0158c6c91' 
  AND token = 'wtPxtMp7aySKUaRTXL8bYQpnvYalPI9ES51ROWtN7K4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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