SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eab137518ef749fa2e6edad29d749e59f3f6130e12befb144da45db3ba50bedf' 
  AND token = 'K5nkLFtAvqzATmZrrAL+ViS11QmixMqz8SCj6CDyBhk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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