SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd0034867734bf1abd3168995a71e2348e85ae3d60ad7da3af283725d2a0803b2' 
  AND token = 'OdNRIzmmTv9ygC9KTT8054w3e92X2sNCk2SzFrAs2fQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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