SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd60c037592aa12a5390ce75cf0513b791d9449830fcf9ab3b617f8b1699bcd76' 
  AND token = 'BqM28w80mN+AHaLwHZxJzDL+DgpPtL4P7SR3YpRKC00=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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