SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1607021c83bdae2583a2ff0c132d89f04106a9dabe8b48f6c14ee1c958198502' 
  AND token = 'faHKCNPasVRbkP2vcGik2Nbk+b2iSe6Qz8B3acfe/Rc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00056

JSON explain

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