SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2bafc70e818447595a8c743b503790f29ebd385721941944f025042b6022ef6a' 
  AND token = 'f+raKTwIBT1NYpPORIpeePP4SAmf0qNFMkEgxFeZPww=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}