SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4080c080f1523677adf2c25597fe5a32d3f1143faed4c0d3a95e8bb9dab69573' 
  AND token = 'FEUEij+WhHMUuPljR8NujMKZVLABov92+2lge5ZDv+0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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