SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f8d11a7d18788826aaf413ee53c1759a51fce0e6c7dbb705e998a4ea8fd160c' 
  AND token = 'FhGO1zD4bvDu8CtQvtzOojVcK2XR8fR36gBWkytfK0c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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