SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a9c99d32b321b0353a148a6ba64d3211cf201e30bac7166813279beb03dbcc7' 
  AND token = 'VN2cewA1YAqyZwIh3u7RAzkGg2uVPBfR5qjuc6qcirA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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