SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f158f59c1efb389c02a33faa80a2b1ff3c8f4b9d55b13b522323e3445fd1a8e9' 
  AND token = 'b1zNsvxTxRDTi5BjEExcR2F6oIJXyTHYG74EO7SBImg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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