SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c09ce6bbd942814766d6cac1de3d7d8ead518ab24d4855aabee0039bc8be9d24' 
  AND token = 'n0+Y5EumjefozeVoLhR5xeyEhjHGdQrVSJsjh+mvAAA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}