SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e242e3e889ca7d8b4a73a47917d8a2a1b4d09a3a33175d4752e943f00859f6c1' 
  AND token = '0bgzyCdJnD0g+w0pHxnufxaql9SzjPA2TziAwqEDHP8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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