SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '973e4960f08f1553fa5adbb807befed180f49ab979f020b72368b22cacce53a7' 
  AND token = 'MeWslxGVrL5yTwiICoST4B6r716WoSKEusQkJ8DUpOY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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