SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1fa1a0f3ebc8f3c5018596e183a80fa6c9adead8e9343410a7a43b17a95dc869' 
  AND token = 'twkCygc/XJZD3tBmHLescddfZBMbp6olNKlZIsxmaQo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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