SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cfd59e591a66b83581f9e44fa4372669da5bed33923595f116936172dbdb1c52' 
  AND token = '+pakSfrM8gB8UCfhIE3JEzW2XouFvCU+4l3Zv7kl2qQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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