SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47d8f619eb2afb82285d3d84daeade6629dc201a5b365e1d500c4a0cbb0dfce6' 
  AND token = 'tVF0jQcjCMLS8vTqkqo2lZCsP0ku4/YeSsvI61Dsb9c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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