SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4269f157b405ddabeb6ed3cb5eeef95bc98a4ce0d365872b1941606037c9ab1d' 
  AND token = 'YnAS1vIeAXoNi1Yi2C8s+uRGU1i7aTXP0Gqyz6lib2c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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