SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '39b04008003c1f2dfa55967993432ebea3bf5bbb7ae586eaf84faff6a46b5ff7' 
  AND token = 'F25kGdF+yQk03/IzPrGMuPqfNC0fzoNP7CynzbejPfQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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