SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa684a826a273f2cb5160308828c50cd0377dd3d835d33577aec1accd61d4e5e' 
  AND token = 'yRiHAOPpZzCXoo1jBXDqjJDLTkk8+QNibq/FQYQPOHA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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