SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd6d49b9a819e6788aab0b7369655008ceca8554b4cff143525fa59bf437d8c25' 
  AND token = 'jpgv/19hkDG5+tsgyYn7zNveW4T2GKGLDsJTtXOUUGE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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