SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd0c606ecbd8288eb5a5ee73963227b065b991296cce7bcfbd1d2e7ac55d2fd3c' 
  AND token = 'BaWia+Aox3H6KjhQJI6evpFfP4jRu8Nz43ixJsjJ8hg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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