SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b0eaa401f8728cf75468488a0a9e6ebeb2da0821af6574d6efafb41dfb7d08ec' 
  AND token = 'AGwaDohrBDqDN769p+QrWi9BtkPzhWyUAOjgENBnkHc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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