SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72a82e05ccaf97fcda8096a7b0cb7c5b7712eddd6983a1bb80c4c3695d849722' 
  AND token = 'GK5au5bNuZCHDoi8BrUIoWdv/pTFMllvVuFzwH/gAtU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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