SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41e28c03824c5d14a4d931c0215e50921be5676e9c9ecccbe444c7936e23cc8e' 
  AND token = 'RIMRvME2oJnYeurxzX5lh997P4qbT9eKt/pfz1YBOjY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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