SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '23ba24ef42066ffa671c7ec0ef66d83c5ca2d765f00d16129ea717007e00fdf4' 
  AND token = 'dwwOdOEfHXnPIEj0rvZzIri0R+b3kmnkaMXpSSBnXe4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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