SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0f15b67e31a8d62179875dfcc0c4e766f20e603461660aae21e8c1f6e4d14949' 
  AND token = 'nvdwp+K4uLZqaayEy+zxhYrZOmZi/wmLRrFFlv5vRPA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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