SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '16c7148bcea0652f3b03f1e996dc714646045aadfd19e438f54bdf5470a79ee6' 
  AND token = 'RJTz2wuGBn3g4m8biZ35wgdBVRK7Si/a0VUgeGDQRNM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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