SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '58576afd7d0d27a3f8023502beff92ab137784f2ac98b1d9cadaa9d9569b721d' 
  AND token = 'BFKDEqQexJurgBoIbdr8R0y4zv4LcZDe6rwAOdlK6CA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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