SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'bed950748236d7d625cd8720ac3b463474d6f0c0ac10a90659f32fff0a5c2386' 
  AND token = '6/er206M15qABKK1Ur/495/X5qLKg8vi48z2jndhxgw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00069

JSON explain

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