SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7af247bcd64410316b5da65dfd63ceb0c77d4d0f8de6bf1e5798d725b1024400' 
  AND token = 'sqZBF+5u2DFw6leKbKBEOx2WnkdPot2Ou2D5PHQbaF0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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