SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '02748a9e246eabeb63ae7096238d9b11d405be18241cf719cf81c6e3b69e3645' 
  AND token = 'Mw/mBL+pYhzf1SlY88f+EAL3VTPLosNZvgYglZ0n33o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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