SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '33bb7931ce94b9918c1f2c188dd824b06b2944c72b0389f1cdf5aa3bddf746b0' 
  AND token = 'vqnQS5fg2smUIHhH4zuqjfeqVGzqMXMX8gTtMVaDEmA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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