SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9fd06f6246285e6662021a9aeb2b9c894b7933ce2b44eff02271331701efd4f8' 
  AND token = 'iJeCIPYvCaLASo8S21PSXkExUTUO96JfkwLSVadW2PE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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