SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '90458342f99c8a488db5e7e9e3890a8458954ecad0652f9bbb47e0389f8a83e9' 
  AND token = 'yAXN3gdnnrO6hcKVXZ0x7OtIKVpEtEnO58M/wwrsYJ8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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