SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '935aa431966295b3b81144276e6ff9eb68611f4ac585cda8127cb1ae4433633e' 
  AND token = 'GLZZ/oyZVahErZUzwDMVOeppaDCylhvfDFH55TY6Mns=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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