SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '93595d0278ca5f8009de68d0c623004b96c17acc377abd2727afacc04348779b' 
  AND token = 'mtyiyP4aRH9gKNSBF+jD/wvhSA2f9mXegzvqLhJuiBQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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