SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'f258dae85a78346569dd8e11a37f90abf0f262d4ef643482f195703ec3c0739f' 
  AND token = 'CjPDFD0IiP09do2xVXtpkhF47G3YLM6PrH4laRxVvvc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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