SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '26035f150bcd754b8749922b688a22e5fb6d0e5d56ddd7ec017bf4a9af353b01' 
  AND token = 'HLVWkZRLZgZ4lUEAqfUVI6SP/amJxF86jwoarxoNwYA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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