SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '139b390b585444e5547b242cc06906d02ba4e874ec2a8f84959b8e1318b99f60' 
  AND token = 'gPJLuZQVXvvJ81/LcAIVsDIF5tGmdnZK7cd0fb+z/aU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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