SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89097a945375b4db6464d15223f055ea252593118fb99f0fbe61fd823aead38d' 
  AND token = 'gEhLW3M+y4eZZMmRtuM3aXqrg2d5YvBLqMXm5eW2cWI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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